MICROBIOLOGY OF INFECTED ATOPIC DERMATITIS

Background. Bacterial infections occur frequently in lesions of atopic dermatitis (AD). The objectives of the study were to establish the aerobic and anaerobic microbiology of secondarily infected AD. Methods. A retrospective review was carried out of clinical and microbiology laboratory records and of data obtained from patients with secondarily infected AD lesions, whose specimens of infected sites were processed for the presence of aerobic and anaerobic bacteria. Results. Bacterial growth was noted in 41 specimens. Aerobic or facultative anaerobic bacteria only were present in 15 patients (36%), anaerobic bacteria only in eight (20%), and mixed anaerobic-aerobic flora was present in 18 (44%). Seventy- two isolates were recovered (1.8 per specimen), 34 aerobic or facultative bacteria, 35 strict anaerobes, and three Candida sp. The predominant aerobic and facultative bacteria were Staphylococcus aureus (12 isolates). Group A beta hemolytic streptococcus in five isolates, and Escherichia coli in four. The predominant anaerobes were peptostreptococcus spp. (13 isolates), pigmented Prevotella and Porphyromonas spp. in eight, and Fusobacterium spp. in four isolates. Single bacterial isolates were recovered in 14 patients (34%), seven of which were S. aureus. Twenty-one of the organisms isolated from 16 patients (39%) produced the enzyme beta-lactamase. Organisms that resided in the mucous membranes close to the lesions predominated in these infections. Enteric gram-negative rods and bacteroides fragilis group predominated in lesions on legs and buttocks. Group A beta-hemolytic streptococci, pigmented Prevotella, and Porphyromonas and Fusobacterium spp. were most frequently recovered in lesions of the finger, scalp, face, and neck. Conclusions. The polymicrobial etiology of secondarily infected AD lesions and the association of bacterial flora with the anatomic site of the lesions are demonstrated.     

The neurofilament antibody RT97 recognises a developmentally regulated phosphorylation epitope on microtubule-associated protein 1B

Microtubules are important for the growth and maintenance of stable neuronal processes and their organisation is controlled partly by microtubule-associated proteins (MAPs). MAP 1B is the first MAP to be expressed in neurons and plays an important role in neurite outgrowth. MAP 1B is phosphorylated at multiple sites and it is believed that the function of the protein is regulated by its phosphorylation state. We have shown that the monoclonal antibody (mAb) RT97, which recognises phosphorylated epitopes on neurofilament proteins, fetal tau, and on Alzheimer's paired helical filament-tau, also recognises a developmentally regulated phosphorylation epitope on MAP 1B. In the rat cerebellum, Western blot analysis shows that mAb RT97 recognises the upper band of the MAP 1B doublet and that the amount of this epitope peaks very early postnatally and decreases with increasing age so that it is absent in the adult, despite the continued expression of MAP 1B in the adult. We confirmed that mAb RT97 binds to MAP 1B by showing that it recognises MAP 1B immunoprecipitated from postnatal rat cerebellum using polyclonal antibodies to recombinant MAP 1B proteins. We established that the RT97 epitope on MAP 1B is phosphorylated by showing that antibody binding was abolished by alkaline phosphatase treatment of immunoblots. Epitope mapping experiments suggest that the mAb RT97 site on MAP 1B is near the N-terminus of the molecule. Despite our immunoblotting data, immunostaining of sections of postnatal rat cerebellum with mAb RT97 shows a staining pattern typical of neurofilaments with no apparent staining of MAP 1B. For instance, basket cell axons and axons in the granule cell layer and white matter stained, whereas parallel fibres did not. These results suggest that the MAP 1B epitope is masked or lost under the immunocytochemical conditions in which the cerebellar sections are prepared. The upper band of the MAP 1B doublet is believed to be predominantly phosphorylated by proline-directed protein kinases(PDPKs). PDPKs are also good candidates for phosphorylating neurofilament proteins and tau and therefore we postulate that the sites recognised by RT97 on these neuronal cytoskeletal proteins may be phosphorylated by similar kinases. Important goals are to determine the precise location of the RT97 epitope on MAP 1B and the kinase responsible.     

Identification of an Unusual Right Atrial Mass as a Chiari Network By Biplane Transesophageal Echocardiography

An unusual right atrial mass was visualized on the transthoracic and single planar transesophageal echocardiograms of a young female patient. Biplane transesophageal echocardiography, however, clearly demonstrated this structure to be a prominent Chiari network. Large eustachian valves and Chiari networks may mimic tumor or thrombus formation when conventional noninvasive diagnostic techniques are used. Multiplanar imaging can be essential in defining anatomical relationships of normal variant structures, eliminating concern for pathological entities and the need for further invasive work-up.     

The Communication Infrastructure as a Social Determinant of Health: Implications for Health Policymaking and Practice

Policy Points

• Persistent communication inequalities limit racial/ethnic minority access to life‐saving health information and make them more vulnerable to the effects of misinformation.
•  Establishing data collection systems that detect and track acute gaps in the supply and/or access of racial/ethnic minority groups to credible health information is long overdue.
• Public investments and support for minority‐serving media and community outlets are needed to close persistent gaps in access to credible health information.

     

Urinary tract and genito-urinary suppurative infections due to anaerobic bacteria

Anaerobes have been involved in many different types of urinary tract infection. This review describes the microbiology, diagnosis and management of urinary tract and genito-urinary suppurative infections caused by anaerobic bacteria. The types of infections of the urinary tract in which anaerobes have been involved include para- or periurethral cellulitis or abscess, acute and chronic urethritis, cystitis, acute and chronic prostatitis, prostatic and scrotal abscesses, periprostatic phlegmon, ureteritis, periureteritis, pyelitis, pyelonephritis, renal abscess, scrotal gangrene, metastatic renal infection pyonephrosis, perinephric abscess, retroperitoneal abscess and other infections. The anaerobes recovered in these studies were Gram-negative bacilli (including Bacteroides fragilis and pigmented Prevotella and Porphyromonas sp.), Clostridium sp., anaerobic Gram-positive cocci and Actinomyces sp. In many cases, they were recovered mixed with coliforms or streptococci. The recovery of anaerobes requires the administration of antimicrobial therapy that is effective against these organisms. These antimicrobials include metronidazole, chloramphenicol, clindamycin, a carbapenem, cefoxitin and the combination of a penicillin and a beta-lactamase inhibitor. Percutaneous drainage, open surgical drainage or nephectomy might be indicated for abscesses.     

Pseudoatrial Flutter: Artifact Simulating Atrial Flutter Caused by a Transcutaneous Electrical Nerve Stimulator (TENS)

A patient with previous actual atrial flutter had what appeared to be atrial flutter seen on Holter monitoring during treatment with a transcutaneous electrical nerve stimulation (TENS) unit. This proved to be artifact caused by the unit rather than a true arrhythmia. The artifact was reproduced in a normal volunteer by application of a TENS unit.     

Horizontal Plane Transesophageal Echocardiography May Be False Negative for Large Tricuspid Vegetations

A 37-year-old man was admitted to the hospital with fever. Because of a history of intravenous drug abuse, and a picture consistent with septic pulmonary emboli, right-sided endocarditis was suspected. However, transthoracic echocardiography did not reveal any vegetations. Transesophageal echocardiography was therefore done, and excellent visualization of the tricuspid valve with the horizontal plane view showed what appeared to be a normal tricuspid valve. However, the vertical plane image clearly showed a large tricuspid vegetation. This case illustrates the advantage of the biplane transesophageal transducer, as the diagnosis would have been missed with a standard single plane probe.
transesophageal echocardiography, tricuspid vegetation, biplane transesophageal echocardiography     

ECTOPIC FUNCTIONING ADRENOCORTICO-MYELOLIPOMA IN LONGSTANDING NELSON''S SYNDROME

A 26-year-old man with the Nelson's syndrome is described, in whom an abdominal tumour developed, accompanied by recurrent Cushing's syndrome 11 years after total adrenalectomy. Upon removal the tumour was a myelolipoma containing islands of adrenocortical-like elements. On incubation of the tumour with radioactive precursors, its capacity to produce cortisol in vitro was shown. The name adrenocortico-myelolipoma is suggested for this tumour.     

Diastolic Left-to-Right Shunting in Uncomplicated Ventricular Septal Defect

The systolic left-to-right shunt in patients with uncomplicated ventricular septal defect is associated with a classic loud murmur, and is well described. The additional diastolic left-to-right shunt, always silent, is less well recognized. Left-to-right diastolic shunt flow is directly related to the defect size, to the diastolic pressure gradient between the left and right ventricle, and to the duration of diastole. The purpose of this study was to evaluate by Doppler echocardiography the duration, magnitude, and flow velocity characteristics of the diastolic left-to-right shunt. There were 30 adult patients with uncomplicated ventricular septal defects studied by color, pulsed, and continuous wave Doppler echocardiography. In each patient, the uncomplicated ventricular septal defect was visualized by two-dimensional echocardiography and/or Doppler echocardiography, and the systolic and diastolic left-to-right shunt flow was identified by Doppler echocardiography. Accurate Doppler flow velocity peaks twice, in beginning and again at end diastole. The mean diastolic flow velocity was 0.5–1.5 msec (average 0.83 ± .22 msec). This flow velocity was markedly lower than the mean systolic shunt flow velocity (2.4–5.3 msec, average 3.8 ± .7 msec). The Doppler flow velocity integral was 0.17–0.64 m (average 0.36 ± 0.14), markedly smaller than the systolic flow velocity integral (0.8–1.8 m, average 1.3 ± 0.3). The diastolic left-to-right shunt flow was 12–41% (average 21 ± 8) of total (systolic and diastolic) shunt flow. In conclusion: Diastolic left-to-right shunts can be identified in all patients with uncomplicated ventricular septal defects, and analyzed in the majority of patients. A significant degree of the left to right shunting in uncomplicated ventricular septal defects occur during diastole.